This invention relates generally to a humidifier and, more particularly, to a humidifier with a liquid tank having a leakage control cap.
Many present day humidifiers employ bases that define a liquid filled reservoir in which water is heated to evaporation temperature by a suitable heating unit. Water is usually supplied to the reservoir by a tank removably supported by the base. Typically, the supply tank includes a bottom wall that defines a fill opening and a discharge spout that projects downwardly into the liquid reservoir in the base. During use, the supply tank is filled with water through the fill opening which is then closed by a removable cap. The filled tank is then inverted and positioned on the base after which water is supplied to the base reservoir through the discharge spout. The level of water maintained in the base reservoir is determined by the projection thereinto of the discharge spout and existing fluid dynamics of the system including weight of water in the tank, surface tension of water, vacuum pressure produced in the tank, atmospheric pressure above the liquid in the base reservoir, etc. When the water level in the reservoir drops below a predetermined desired level a pressure imbalance evolves across the discharge spout allowing air to enter the tank and a resultant water discharge therefrom to again create a pressure equalization and the desired water level. However, inadvertent water leakage through the removable cap in the fill opening will produce an undesirable increase in water level that can result in water spillage and inefficient humidifier operation. Another problem of prior humidifiers is an inability to provide a tangible indication of proper operation.
The object of this invention, therefore, is to provide an improved humidifier that alleviates problems associated with tank leakage and provides a tangible indication of proper operation.